This is a note to let you know that I've just added the patch titled drm/dp/mst: Reverse order of MST enable and clearing VC payload table. to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-dp-mst-reverse-order-of-mst-enable-and-clearing-vc-payload-table.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c175cd16df272119534058f28cbd5eeac6ff2d24 Mon Sep 17 00:00:00 2001 From: Andrey Grodzovsky <Andrey.Grodzovsky@xxxxxxx> Date: Fri, 22 Jan 2016 17:07:29 -0500 Subject: drm/dp/mst: Reverse order of MST enable and clearing VC payload table. From: Andrey Grodzovsky <Andrey.Grodzovsky@xxxxxxx> commit c175cd16df272119534058f28cbd5eeac6ff2d24 upstream. On DELL U3014 if you clear the table before enabling MST it sometimes hangs the receiver. Signed-off-by: Andrey Grodzovsky <Andrey.Grodzovsky@xxxxxxx> Reviewed-by: Harry Wentland <harry.wentland@xxxxxxx> Acked-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/drm_dp_mst_topology.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -1976,6 +1976,12 @@ int drm_dp_mst_topology_mgr_set_mst(stru mgr->mst_primary = mstb; kref_get(&mgr->mst_primary->kref); + ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, + DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); + if (ret < 0) { + goto out_unlock; + } + { struct drm_dp_payload reset_pay; reset_pay.start_slot = 0; @@ -1983,12 +1989,6 @@ int drm_dp_mst_topology_mgr_set_mst(stru drm_dp_dpcd_write_payload(mgr, 0, &reset_pay); } - ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, - DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); - if (ret < 0) { - goto out_unlock; - } - queue_work(system_long_wq, &mgr->work); ret = 0; Patches currently in stable-queue which might be from Andrey.Grodzovsky@xxxxxxx are queue-4.4/drm-dp-mst-reverse-order-of-mst-enable-and-clearing-vc-payload-table.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html